Grab bar



FIG. 1 is a top, front, and right side perspective view of a grab bar showing our new design;

FIG. 2 is a front elevational view thereof, the rear being a mirror image of that shown;

FIG. 3 is a right side elevational view thereof; and,

FIG. 4 is a top plan view thereof.

The broken-line disclosure is represents unclaimed portions of the article in which the design is embodied, but forms no part of the claimed design, and the vertical broken line most prominent in FIG. 2 represents the unclaimed boundary between the claimed and unclaimed portions of the article. 

The ornamental design for a grab bar, as shown and described. 